I made something similar to what is shown in the link in Skylar Cook's post above. I'll call it a "GHD piece" - this gets put on top of what I use for box jumps (basically something like a sawhorse, but wider on top), and I hook my feet under a metal pole clamped to my squat rack (I've taped some foam around that where you hook your feet). The "GHD piece" that I made is not as tall as shown in the link - it is basically just the curved part (and more of an oval shape, rather than a semi-circle) without the straight sides underneath. I think this makes it more stable. I find that this stays on the box by itself without needing any sort of attachment.

The "GHD piece" is a number of sections of scrap plywood cut into "D" shaped sections with a jigsaw. Precision in the cuts isn't important as after gluing together, you cover with thick foam rubber, cover that over with vinyl and staple that to the wood. Dimensions rougly 12 inches (wide) x 10 inches (deep) x 6 inches (high). Works fine for a home gym, and takes up no more space than is already taken up by the box-jump box.

I've been using a swiss ball and anchoring my feet against the pad on a leg extension machine - the only use I've found for one so far. Takes about 5 seconds to set up, works well for back extensions, situps etc. Failing that, I lower the bar on a smith machine to a suitable height - The only good use for that also! Only downside with a ball I always have to do some arranging of anatomy however, to avoid a mid-set debilatating mishap.

I was actually just thinking about building something like this myself. I got the idea from those Bosu ball chairs. Now I'm thinking now about building something that could slip over a jump box and try to maximize use of equipment and minimize space usage. Definitely cheaper than a $835 unit which is not an option. Hell a standard GHD is only around $300 or so.

Funny the thought of using a plyobox as a base has crossed my mind too. I've been tossing around a couple of ideas. If some engineer on here beats me to the punch, I'm not to shy to say nice work and send me your step by step.

Yeah, cost is definitely prohibitive. But as of late, I quit my globo-gym and am trying to slowly acquire everything that I want. I'm really just building a long term wish list.

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